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Affinity Electrophoresis May 11 (Wed.) 10:25 - 10:45 Affinity Electrophoresis May 11 (Wed.) 10:25 - 10:45 MICROHETEROGENEITY OF GLYCOPROTEINS T . C . B\2l g - Hansen The Protein Laboratory , University of Copenhagen , Denmark Affinity chromatography and electroimmunoprecipitati on can be combined to obtain analytical procedures with the following aims: To identify ligand- binding proteins , to characterize the binding with respect to structure and number of binding sites and the association constant, to quantify individual carbohydrat e f orms of microheterogeneolls glycoproteins , and to predict the results of preparative affinity separations . The following methods were developed to study glycoproteins with lectins , and they differ in the order in which proteins interact with lectins. In Method A the sample is incubated with l ectin before analysis by crossed immunoelectrophoresis . In Method B free lectin or immobilized l ectin is incorporated in an intermediate gel in crossed immunoelectrophoresis . In Method C free lectin or immobilized lectin is incorporated in the first dimension gel of crossed immunoelectrophoresis . By comparing with c ontrol experiments it is possible to identify and charac­ terize protein-lectin interactions by differences in electr opho­ retic and antigenic behavior of the protein under study. Protein lectin interaction can then be studied by comparison of the electr ophoretic and antigenic behavior of the proteins under study with the results of control experiments . Using these methods we have found that the microheterogeneity of serum glycoproteins is remarkably constant in normal indivi­ duals , but is changed characteristi cally in disease . Examples of quantitation of microheterogeneity forms of disease markers will be mentioned (eg. AFP , ferritin , AGP and other acute phase p r oteins ) and their biological significance will be discussed . Memo : - 46 - Affinity Electrophoresis May 11 (Wed.) 10:45- 11:00 ELECTROPHOR ETIC PROPERTIES OF RCA-2 BINDING GLYCOPROTEINS IN HUMAN SERA AND ASCITES WITH HEPATOCELLULAR CARCINOMA M. Fukushima, T. Arima, F. Suwa, J. Watanabe, N. Koide, and H. Nagashima The First Dept . of Intern. Med . ,Okayama Univ . Med. School, Oka­ yama 700, Japan. Gl ycoproteins associated with hepatocellular carcinoma , which have Gal or GalNAc at their non-reducing end, were determined by hemagglutination inhibition test, in patints' sera with di­ gestive diseases, and these glycoproteins were purified with RCA - 2- agarose and anti-whole human serum-Sepharose 4B affinity chromat ographies . Their e lectrophoretic proper ties were analysed with SDS-polyacryl amide gel electrophoresis(SDS- PAGE). For the determination of RCA-2 lectin binding glycoproteins, 25pl of sample which had been appropiately diluted with Gelatin Veronal Buffer (GVB) were mixed with 25~1 of human O-type RB C (1.5% Ht) and 25 11 1 of RCA - 2 le c tin(50~g/ml), and the mixture was incubated at 37°C for 60 min to check hemagglutination inhibi­ tion. 10 ml of ascitic fluid(170 mg protein) which had been ob­ tained from a patient with hepatocellular carcinoma were applied to a column(lX14 cm) of RCA-2-agarose(4 mg/ml of RCA-2) and RCA -2 binding glycoproteins were eluted with 0 . 3M B- lactose after washing the column with GVB . The eluate was then passed through a column(1.6X28 cm) of anti- whole human serum-Sepharose 4B(15 mg Iml of IgG) to absorb normal serum components. Glycoproteins thus prepared were subjected to SDS -PAGE(7 . 5%) electrophoresis. RCA-2 binding glycoproteins in the serum were detected in 10/ 21(47.6%) of hepatocellular carcinoma, 9/22(40. 9%) of liver cir­ rhosis, 1/20(5.0%) of chronic hepa titis, 1/10(10%) of acute he­ patitis and 18/23(78. 3%) of malignant digestive diseases other than hepatocellular carcinoma. 160 ml(2 . 7 g of protein) of asci­ t es were applied to the affinit y c hromatographies successively and 3 . 6 mg of glycoproteins were prepared . SDS-PAGE of the preparation showed only one main band(48K daltons). Memo: - 47- Affinity Electrophoresis May 11IWed.) 11 :00 - 11:15 SEPARATION AND IDENTIFICATION OF DIFFERENT MOLECULAR SPECIES OF HUMAN a-FETOPROTEIN BY DOUBLE AFFINITY ELECTROPHORESIS WITH CONCANAVALIN A AND LENS CULINARIS HEMAGGLUTININ A K. Taketa and M. Izumi Health Research Center, Kagawa University, Takamatsu, Japan. H. Nakabayashi and Jiro Sato Division of Pathology , Cancer Institute, Okayama University Medical School, Okayama, Japan. Human a-fetoproteinIAFP: in body fluids is usually composed of various proportions of distinct molecular species with different affinities to concanavalin A(con-A) and Lens culinaris hemagglutinin A(LcH-A). This was demonstrated by isolation of each molecular species with Con A-Sepharose and LcH Gel in column chromatography and by crossed-immuno- affino- electrophore­ sis for determination of dissociation constants of AFP-lectin complexes. AFP 1 had no affinity to either con-A or LcH-A, AFP 2 strong affinity to con-A but weak or no affinity to LcH-A, and AFP, strong affinity to both of the lectins. AFP. was a major component of cord serum AFP, and AFP 2 and AFP 3 were variable components of AFP from hepatocellular carcinoma or its cultured cellline(HuH-7). An additional species of AFP found in the medium of HuH-6 Cl-5 had weak affinities to both of con- A and LcH-A. These molecular species of AFP were also separated a nd identified from their relative mobilities by double affinity electrophoresis with con-A and LcH-A, in which these lee tins in separate agarose gels were connected serially in alternate orders(LcH- A ~ con- A and con-A ~ LcH-A). Simplicity of this method for one-step separation of major molecular species of AFP in biological materials was thus demonstrated. This work was supported by Grant-in-Aid from the Ministry of Education, Science and Culture(57570836). Memo: -48- Affinity El ectrophoresis May 11 (Wed.) 11 : 15 - 11 :30 CROSSED IMMUNOELECTROPHORESIS FOR THE DETECTION OF SPLIT PRODUCTS OF THE THIRD COMPLEMENT IN DENGUE HEMORRHAGIC FEVER . I . OBSERVATION IN PATIENTS' PLASMA V. Churdboonchart, N. Bhamarapravati and P . Futrakul Dept. of Pathobiology, Faculty of SCience, Mahidol University, Bangkok, Thailand. Crossed Immunoe l ectrop horesis (CIEP) was applied to detect the products of the third component of complement (C 3 ) activa­ tion in plasma of patients who suffered from Dengue Hemorrhagic Fever (DHF) which is caused by dengue viruses types 1,2,3 and 4 . First dimension electrophoresis was performed using 5xlO cm gl ass slides with 6 ml of 1% agarose in 0.01 M EDTA-Tris buffer pH 8 . 6 . Samples, 1 ~l for each test, were placed in to 1 mm punched wells. The electrophoresis was done by using 10 v/cm in 4'C for 60 min. Second dimension electrophoresis was run per­ pendicularly in rabbit anti-C3 serum containing agar ose and electrophoresis was performed by using 2v/cm 4 ' C overnight. Normal human serum treated with inulin, a known C3 splitting agent, was used as positive control in all tests. C3 split·· produc ts (C3sp) were demonstrated in severely ill patients clinically c l assified as the grade III and grade IV, and rapidly disappeared during convalescent phase . The appearance of C3sp correlated well with the signs of shock, and this e lectropherogram of C3sp could be used as a parameter reflecting immunological activity in this disease . Memo: -49- Affinity Electrophoresis May 11 (Wed.) 11:30-11:45 AFFINOPHORESIS OF TRYPSINS. ELECTROPHORES IS OF TRYPSINS IN THE PRESENCE OF A SOLUBLE POLYELECTROLYTE BEARING AFFINITY LIGAND. K.Ka sai and K.Shimura Dept. of Biological Chemistry, Faculty of Pharmaceutical Sciences, Teikyo Univ., Sagamiko, Kanagawa, Japan. We devised a new separation technique for the protein, "affinophoresis", which is based on its specific affinity and utilizes electrophoresis . This technique requires a carrier molecule, "affinophore", which contains both an affinity ligand for a certain protein and man y charges, either positive or negative, in order to migrate rapidly in an electric field. When a mixture of prot eins i s e l ectrophoresed in the presence of the affinophore, the protein having an affinity with the ligand wil l form a complex with the affinophore. This results in a change i n the apparent e l ectrophoretic mobility. If the prot ein is sufficientl y acce l erated, we can separate it from other materia l s. A cationic affinophore for trypsin was prepared. So luble dextran (MW 10,000) was coupled with a DEAE-group and m-aminobenzamidine, a comp etitive inhibitor of trypsins . Electrophoresis of trypsins from several origins on agarose ge l plates in the presence of the affinophore showed that affinophores is actually occurred . The e lectrophoretic mobilities of trypsins increased towards the cathode , the same direction as the affinophor e movement. The presence of l eupeptin and treatment of the trypsins with TLCK suppressed the effect of the affinophore . Streptomyces griseus trypsin, contained in Pronase, was easil y separated and detected. This procedure i s distinct from affinity chromatography and so- called affinity electrophresis in that the support of the affinity ligand move s , and has advantages especially for analytical purposes: for example, t he det ection of specific molecules r egardless of t heir isoel ectric points . Memo: Th is abstract is the same as PS-3-27. - 50 - Affinity Electrophoresis May 11 (Wed .) 11 :45 - 12 :00 HETEROGENEITY OF RABBIT ANTI -DNP ANTIBODY STUDIED BY TWO-DIMENSIONAL AFFINITY ELECTROPHORESIS K. Takeo, R. Suzuno, T. Tanaka, M. Fujimoto, A. Kuwahara, and K. Nakamura Dept. of Biochem., Yamaguchi Univ. Sch. Med., Ube, Japan Rabbit anti-Dnp antibody was separated two-dimensionally in the first direction by isoelectric focusing(IEF) and in the second direc tion by affinity electrophoresis(AEP) . Rabbits we re immunized with Dnp-human-yg-globulin. The anti Dnp antibodies were purified by ammonium sulfate fractionation followed by affinity chromatography with a Dnp-lysyl-Sepharose column.
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